Suckermouth catfish may refer to:
- Any species of armored catfish (family Loricariidae), most notably:
- Hypostomus plecostomus, and Hypostomus punctatus, two species of armored catfish popular with aquarists
- Any similar species marketed under the name "plecostomus" or "pleco"
- Sailfin suckermouth, usually Pterygoplichthys gibbiceps